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AF447

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I know it’s Vanity Fair….but excellent

YPJT, United Arab Emirates

Brilliant – and scary.

PS: nothing wrong with Vanity Fair, they employ some of the best writers – and Langewiesche is one of them. Not sure if he’s related to THAT Langewiesche, though.

One of the comments states that he’s his son.

And here we go:

http://en.wikipedia.org/wiki/William_Langewiesche

Last Edited by kwlf at 25 Sep 06:04

That’s a very good article.

If one was to look for just one factor, I would say it is a lack of aircraft systems knowledge. They should have known that the pitch indication, the altitude and the engine power indications are not likely to be wrong.

The bit on the captain’s girlfriend being around and he having had almost no sleep the previous night is very interesting. No wonder he was keen to get some sleep.

Administrator
Shoreham EGKA, United Kingdom

I’m not so sure about systems knowledge being the major factor. Langewiesche writes that it took the crew 11 seconds from A/P disconnect to figure out that the air speed indications had failed, which is a reasonable time.

The big question is why didn’t they leave well alone? Failure of air speed indication in cruise is not something that demands immediate action.

ESKC (Uppsala/Sundbro), Sweden

I am sure he won’t mind. He has posted this on several forums…….

Just posted this in another forum, might as well repeat it here.

The cause of this accident was the non-pilot in control of the aircraft from the right seat. He was VERY nervous about being IMC in the tops, with TRW ahead that he didn’t know how to avoid (maybe didn’t know how to work the radar). He wanted desperately to get on top.

When things went to hell, he panicked, and pulled back on the side-stick, apparently for all he was worth. Due to the NUTTY design, the non-pilot in the left seat had no idea what was going on, and was likely fixated on the airspeed problem.

When the airspeed went south, they froze in fear, and a BILLBOARD in the cockpit saying “GET THE NOSE DOWN” wouldn’t have helped, they were simply buried in bells, whistles, horns, clackers, “Vive le France,” and a multiplicity of warning lights.

They had NO IDEA they were in a “Deep Stall,” and almost certainly didn’t even know the term, or that the “maneuver” existed!

The sleeping captain reacted very quickly, I doubt that I could have made it to the cockpit. When he did, he accurately said “We’re in a stall,” but with no idea of the history, he had no chance, and there was simply no time left.

I’d bet a chocolate chip cookie that I may be the only person reading this who knows from personal experience what a “Deep Stall” really is. Not bragging, it’s simply something that is not taught, and it’s very likely to be fatal if you get into one.

When I went for the MES rating in about 1960, the only place I knew to get it was with “George Lambros,” who owned a Grumman Widgeon he operated out of the Teterboro Seaplane base (now defunct?). He was also the instructor, and the designated examiner, and had thousands of hours in it. He was also kinda crusty. His standard procedure was one flight, four hours long, with every seaplane/amphibian/landplane maneuver known to man, and a few that were not. His statement, repeated several times on the phone and in person a couple of times, “If you forget the gear check (“Water landing, gear up” or Land Landing, gear down”) or got the gear wrong, the check ride is a bust, and you’ll have to come back and do it all over again, including the $495, all-inclusive fee.” There was no doubt in my mind he meant it.

First instruction was “Fly UNDER that bridge” (the George Washington Bridge). “It’s your ticket, not mine,” I said, and did so. We then had fun, and it was fun. Except the one unexpected, unbriefed maneuver. We’d done the stalls, had climbed to 8 or 9,000’ again, and he finally said “Lay into it hard, maybe 45 degrees nose up, cut the power, and hold full back stick when it breaks.” I thought he was still trying to scare me, so I did that, too. After the break it got kinda quiet, very low RPM (wooden fixed-pitched props), and then he said “recover.”

I tried, I really tried. Airspeed was showing off-scale low, nose would come down just a bit, but as soon as I tried, it would just come back to level. Finally pushed all the way, nose came down a little more and stopped, no airspeed.

“Open your window, and stick your hand out.”

I did, and was astounded that the relative wind was blowing my hand STRAIGHT UP. He was laughing fit to be tied. “Push the stick full forward, and give it a blast of power, and HOLD IT there. We were now passing 3,000’ or so, and I was concerned. Really concerned. I pushed full forward and gave it blast of power, and the nose came down a lot, maybe to 45 degrees. I started to relax back pressure and power but he said, “HOLD IT.” I did, and finally the airplane went vertically nose down, shook a little, and all of a sudden the airspeed came alive. “HOLD IT to about 80 knots, and recover very gently.”

I was a little pissed, and said “What happens if one or both engines quit?” He didn’t have an answer for that, and filled out the temporary kinda quietly.

It would be years later that I read the Accident Report on that BAC-111 (?) and found out the name of it, a “Deep Stall.” It was their first time, and their last. I think they belly-flopped at 31,000 FPM, making a BAC-111 shaped crater.

Little different on that AF447. They had full power all the way, giving the airplane some forward progress. But there’s no doubt in my mind that they would have had to get the nose down to at least 60 degrees to align the airflow with the angle of incidence before it would begin flying again. And HOLD it there for a bit.

Fly safe. I want this thing to land l...
EGPF Glasgow

Except “deep stall” only happens to certain T Tail aircraft when fully stalled. The turbulent flow from the wings completely blanks the horizontal tail meaning recovery is physically impossible. That is not the case for the A330.

There was a theory advanced by the BEA in the report that is little mentioned – that Flight Director commands were intermittently on display and in the early part of the upset PF was trying to follow them. Langweische doesn’t discuss it because it doesn’t fit his thesis. He has plenty of form slagging off ignorant pilots and phone seriously contradictory views on the Airbus. See his book on the Hudson where he says the bus saved them all and any ignorant crew could have done it.

London area

Actually there is a way to recover from a deep stall because not all of the flying surfaces are rendered inneffective.

Forever learning
EGTB

Actually there is a way to recover from a deep stall because not all of the flying surfaces are rendered inneffective.

… which is?

Administrator
Shoreham EGKA, United Kingdom

The various Test Pilots who tried it in T-Tail aircraft tended to die (indeed, that is how it was discovered). I have looked at a photo of the Grumman Widgeon, and it is abundantly clear from the configuration of flight control surfaces that it is not susceptible to deep stall. Therefore, what the author of BeechBaby’s post shows us (am I right in thinking it was Langweische?) is that they don’t know what a deep stall is.

Deep stall hadn’t been discovered as a concept when the original Stick and Rudder was written (nor had many other aerodynamic principles), as it is mainly applicable to certain airframe/horizontal stabilizer/powerplant configurations that weren’t used until later.

London area
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